Hydropneumatic pressure booster and welding gun



E. F. PANER HYDROPNEUMATIC PRESSURE BOOSTER AND WELDING GUN Filed July 11, 1946 2 Sheats-Sheet 1 INVENTOR. [1mm fiA m ATTOK/Vf) Jan. 31, 1950 E. F. PANER 2,496,104 I HYDROPNEUMATIC PRESSURE BOOSTER AND WELDING GUN IN VEN TOR.

[AME/P f. 5/1 19? BY A TTOK/Vf) Patented Jan. 31, 1950 UNITED STATES PATENT men I-IYDROPNEUMATIC ranssunn BOOSTER AND WELDING GUN Elmer F. Paner, Detroit, Mich.

Application July 11, 1946, Serial No. 682.816

2 Claims.

This invention relates to welding equipment and more particularly to electric welding apparatus of the spot welding type in which repeat operations are effected by fluid pressure in controlling the movement of electrodes of a spot welding appliance. An object of the present invention is to provide a double acting, hydraulically operated apparatus which liminates destructive burning and pitting at the point of the weld by reducing arcing to a minimum.

Another object of the invention is to provide a pressure booster mechanism for the hydraulically operated electrode members.

Another object of the invention is to apply a uniform pressure between the electrode at all times regardless of variations in the thickness of the parts being united by the weld or the wearing away of the electrode tips. 7 A further object of the invention is to provide hydraulic pressure means for advancing the weld-- ing electrodes toward each other and hydraulic pressure means for retracting the electrodes from Welding position.

A still further object of the invention is to p-rovide an improved apparatus for accomplishing this purpose and which permits electric welding operations to be effected more rapidly, thoroughly and easily than has been heretofore possible in a manner permitting better results for the amount of current consumed and also increase the output of the machine, Other objects and advantages of the invention will more fully appear from the following description taken in connection with the accompanying drawings in which:

Fig. 1 is a side view, partly in section and partly in elevation, of the pressure booster portion of the welding equipment;

Fig. 2 is a top plan view of Fig. 1 with a diagrammatic illustration of the pressure input means.

Fig. 3 is a cross sectional view of a portable Welding tool o erable by the booster mechanism shown in Fig .1;

Fig. 4 is a top plan view of Fig. 3 and;

Fig. 5 is a fragmentary sectional view taken on line i5-5 of Fig. 1.

Referring to the illustrated embodiment of the invention, the welding apparatus comprises a booster mechanism shown in Figs. 1, 2 and 5 and a portable welding tool, shown inFigs. 3 and 4 which is operable by the booster mechanism.

The booster mechanism comprises a two part housing, upper portion l0 and lower portion [2,

. 2 the two portions being secured together by bolts M. The upper portion I6 is provided with a. fluid reservoir 16, partially surrounding a cylindrical sleeve :8 forming a cylinder 26. The lower open end of the cylinder is closed by the lower portion ii. of thehousing with a suitable gasket 22 between the meeting faces of the housing portions it and 12. The upper open end of the cylinder 2i! is closed by a head 24 having a fluid inlet passage 26. An air outlet passage is shown at 28 in the lower portion of the housing 10.

The lower portion l2 of the housing has a cylindrical bore 30, longitudinally therethrough and is counter-bored at 32. A sleeve 34 is press fitted in the bore 30 forming a cylinder 36. Thelower portion i 2 is closed by a cap 38.

A piston rod 40, is slidably mounted in a packing assembly 42 press fitted into the counter bore The end of the piston rod in the cylinder!!! is provided with a piston 44 for reciprocation in the cylinder 26 and the oppositeend of the piston rod 46, within the cylinder 36, is provided with a piston 46 for reciprocation in the cylinder 36.

At the upper end of the cylinder 36 and above the piston 46 is a passage 48 communicating with the reservoir l6 through ball check valve 50. The upper end of the cylinder 36 is also provided with a passage 52 leading to the reservoir Hi. The passage 52 is provided with an adjustable spring loaded valve 54, the latter being adjustable by rod 56 projecting through the head 24. This permits a volumetric differential between'the pressures in the-cylinder 36 at the'top of the piston 46' and a smaller chamber, hereinafter more fully referred to.

Referring to Fig; 5 there is a passage 58 forming a communication between the reservoir l6 and the cylinder 36. This passage communicates with the cylinder 36 at a position below the piston 46 when the latter is'at its upper stroke so that fluid may flow from the reservoir l6 into the cylinder 36.

The lower end of the cylinder 36 has a passage 6 communicating with a flexible connection 62 leading to the welding tool. The passage 48 is connected to a flexible conduit 64 leading to the welding tool.

From the above description it will be understood that when a fluid under pressure such as air, is supplied to the cylinder 26, above the pisten 44, through the inlet passage 26, the piston 54 and rod 46 are moved downwardly, exhausting the fluid below the piston through passage 28. Suitable mechanism for controlling flow of fluid pressure, not shown, may be provided. When the fluid pressure is reversed by the control mechanism, that is, by supplying a fluid pressure through the passage 28 and exhausting through passage 26, the piston is moved upwardly. Since the piston rod 40 connects the pistons 44 and 46, the latter moves in unison with the movement of the former. When the piston 46 moves downwardly in the cylinder 36 the fluid pressure below the piston 46 is forced through the flexible conduit 62 and drawn into the cylinder 35, above the piston 46, through conduit 64 and vice-versa upon reverse movement of the piston 45.

Referring now to Figs. 3 and 4, the welding tool is shown having a body portion 66 with a handle 68 and a control trigger for a switch 12. One electrode 74 is removably secured to one end of the body portion 60 by nut 16 and a. fluid conduit I8 is provided for cooling the electrode.

The body portion 80 has a slotted portion 80, between the handle 68 and the outer portion of the body, which receives a carrier 82 pivotally supported at 84 to the body portion 55 between the side walls thereof. The carrier 82 receives an electrode 36 held therein by nut 88. A fluid conduit 90'is provided for cooling the electrode.

The usual cable for conducting the welding current and the cooling liquid is shown at 92 but since they form no part of the present invention, the details thereof are not shown, the same being of common construction which is well known in the welding art.

The carrier 82, at opposite sides of the pivot 84 is provided with oppositely disposed lugs 94 and 60, each of which receives piston and cylinder assemblies A and B. Each assembly comprises a fitting 98 adapted to be press fitted in the lugs 9-5, 96. The fitting 98 has a cylinder I00 with a counter bored portion for receiving a packing :62 around a piston 204 in the cylinder I00. The piston I04 projects outwardly beyond the outer face of a packing nut Hi6 screw threaded to the outer periphery of the fitting S8. The conduits 62 and 54 are respectively connected to the cylinders E09 by nuts I08.

Wear plugs H0, having insulator members H2, are press fitted into the body portion 66 at points axially aligned with the pistons I04.

When it is desired to make a weld, the trigger i0 is pressed, completing an electrical circuit, which controls an air valve, not shown. Fluid pressure is then supplied to the cylinder 20, above the piston d-L'through inlet passage 26. This pressure forces the piston rod 40 and piston 48 downwardly, producing a fluid pressure in the cylinder 35 and in cylinder I00 of the assembly A-through conduit 02. This causes the carrier 82 and electrode 86 to swing clockwise on the pivot 84 bringing the electrodesBE and 14 toward each other for welding a work piece therebetween. As the carrier is pivoted clockwise, the fluid in the cylinder through conduit 64 to the cylinder 35 above the piston 46. Since the piston rod '40 causes a difference in volume of displaced fluid, the valve m0 of the assembly B is displaced 54 compensates for the difference in volume between the cylinder chambers above and below the piston 46.

When the trigger I0 is released, air pressure is supplied to the lower surface of the piston 44, through passage 28. This forces the piston 48 upwardly creating a pressure in the cylinder 35 above the piston 45, which is delivered to the cylinder Hi0 in assembly B through conduit 64, moving the carrier 82 in a counterclockwise direction to separate the electrodes 14 and 86.

From the above, it will be apparent that the construction provides hydraulic pressure means for advancing and retracting the electrodes without the use of springs or other mechanism.

It will be understood that various changes including the size, shape, and arrangement of parts may be made without departing from the spirit of my invention, and it is not my intention to limit its scope other than by the terms of the appended claims.

I claim:

1. An electric welding apparatus comprising a body portion, having a normally fixed electrode, a pivoted carrier on said body portion, an electrode carried by said carrier, a pair of cylinders on said carrier, one each at the opposite sides of the pivot of said carrier, pistons in said cylinders having one end in contact with said body portion, and fluid conduits in communication with said cylinders for alternately conducting a fluid pressure to each of said cylinders.

2. An electric welding apparatus, comprising a body portion having a normally fixed electrode, a carrier pivoted on said body portion, an electrode carried by said carrier, interchangeable cylinder and piston assemblies mounted on said carrier one on each side of the pivotal connection between said body and said carrier, the outer end of said pistons being in contact with said body portion, and fluid pressure means for moving said pistons relative to said cylinders.

ELMER. F. PANER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,153,384 Heany Sept. 14, 1915 1,315,876 Southall Sept. 9, 1919 1,645,705 Ledwinka Oct. 18, 1927 r 2,063,258 Martin Dec. 8, 1936 2,085,105 Lex June 29, 1937 2,126,490 Martin Aug. 9, 1938 2,283,826 Soehner May 19, 1942 2,337,022 Beiderman Dec. 21, 1943 2,341,459 Martin Feb. 8, 19M

FOREIGN PATENTS Number Country Date 525,707 Great Britain Sept. 3, 1940 

